Undecylenoyl Phenylalanine

Synonyms: N-Undecylenoyl-L-phenylalanine, Undecylenoyl Phenylalanine, (S)-2-(Undec-10-enamido)-3-phenylpropanoic acid, Sepiwhite MSH

Undecylenoyl Phenylalanine is a synthetic lipoamino acid that couples an unsaturated C11 fatty acid chain to the amino group of L-phenylalanine. This hybrid structure gives the molecule a dual character: the phenylalanine head interacts with melanocyte-specific targets, while the undecylenoyl tail enhances lipophilicity and skin penetration. The amide bond linking the two moieties is stable under typical formulation conditions, yet the free carboxylic acid group allows for salt formation or ester derivatization if desired.

In the personal care and pharmaceutical industries, Undecylenoyl Phenylalanine serves as a skin-lightening agent and melanogenesis inhibitor. It is supplied as a white to off-white crystalline powder, typically with a purity of ≥98% (HPLC). The material is manufactured via acylation of L-phenylalanine with undecylenoyl chloride under Schotten-Baumann conditions, followed by purification. It is recommended for use in emulsions, gels, and serums targeting hyperpigmentation, age spots, and uneven skin tone.

Research indicates that Undecylenoyl Phenylalanine acts as a melanocortin-1 receptor (MC1R) antagonist, thereby reducing tyrosinase activity and melanin synthesis. It also shows anti-inflammatory properties by inhibiting UV-induced cytokine release. These combined effects make it a valuable active for both cosmetic and dermatological applications. The compound is generally regarded as safe for topical use and is compatible with a wide range of formulation ingredients.

Chemical Structure & Properties

Undecylenoyl Phenylalanine features an amide linkage between the carboxyl group of 10-undecenoic acid and the α-amino group of L-phenylalanine. The molecule has a molecular weight of 331.45 g/mol and a melting point around 120-125°C. It is a white crystalline solid that is soluble in polar organic solvents such as ethanol, DMSO, and propylene glycol, but practically insoluble in water. The presence of the phenyl ring contributes to UV absorbance, which can be useful for stability monitoring. The free carboxylic acid provides a site for pH-dependent ionization, with a pKa typically around 4.5 for the carboxylic acid and near 10 for the amide. The unsaturated fatty chain offers a handle for further functionalization if needed.

Mechanism of Action

• MC1R antagonism: Binds to melanocortin-1 receptors on melanocytes, blocking α-MSH-induced signaling and downstream tyrosinase activation.
• Tyrosinase inhibition: Reduces the catalytic activity of tyrosinase, the rate-limiting enzyme in melanin biosynthesis, by interfering with its copper center.
• Anti-inflammatory effects: Suppresses UV-induced production of pro-inflammatory cytokines such as IL-6 and TNF-α in keratinocytes.
• Melanosome transfer inhibition: May interfere with the transfer of melanosomes from melanocytes to keratinocytes, reducing visible pigmentation.
• Antioxidant activity: Scavenges free radicals, protecting skin cells from oxidative stress that can trigger melanogenesis.

Quality Specifications

Supply & Documentation

• Capacity: 5 metric tons per year
• Lead time: 3-5 business days (stock items)
• Documentation: COA, MSDS, TDS available upon request
• Packaging: 25 kg fiber drum with double polyethylene liner

Request For Quote

• LyvBio Co., Ltd. — Email: info@lyvbio.com